The Substitute 3: Winner Takes All

The SubstituteWinner Takes All is a 1999 action thriller film, the second sequel to The Substitute. The film stars Treat Williams as a mercenary who goes undercover as a teacher in order to expose a college football teams steroidabuse scandal. This movie was later released on DVD in 2000 and bundled with the first movie.

When one of Thomassons students dies from a steroid overdose, Thomasson finally loses his jovial nature, confronting the coach and telling him that he knows how the student died, that he knows the coach is responsible, and that he has audiotape to prove his allegations.In one last showdown, Karl defeats the syndicate and reveals the doping scandalas he leaves, and the credits roll, a radio news report reveals that the football coach committed suicide in disgrace. ........

Source: Wikipedia